ETA (Australia)

Electronic Travel Authority

The ETA is like a visa, except that you do not receive a stamp or visa in your passport. You also don't need to visit an embassy to obtain it. Instead, you can submit an application through a travel agent, airline, or online.[1]

The ETA is valid for 12 months, in which period you can visit Australia multiple times, but never for more than 3 months. Depending whether you are visiting Australia for tourism/visiting friends and family, or you are visiting for business, there are two varieties of ETA, as outlined on the official immigration website.[1] You can not work with an ETA.